In a particular statistics exam, the 10th percentile of final exam score is 59, and the 90th percentile of final exam score is 93. A histogram of the scores approximately follows the normal curve. What is the approximate standard deviation of the final exam scores? Hints: What is the z value in the normal table that gives you closest to 80% of the area between -z and z? Now what does that tell you about the number of SDs in between 59 inches and 93 inches? You might find it helpful to draw a picture of the normal curve with original units and standard units. O 13.1 O 26.2 O 17.2 O 6.5